A Snapback-Free and Fast-Switching Shorted-Anode LIGBT With Multiple Current P-Plugs

Weizhong Chen,Yao Huang,Zhengsheng Han,Shun Li,Yi Huang

doi:10.1109/jeds.2020.3001002

Abstract

A novel snapback-free and fast-switching Shorted-Anode Lateral Insulated Gate Transistor (SA LIGBT) with Multiple Current P-Plugs (MCP) in anode, named MCP LIGBT, is proposed and investigated. The device features Multiple separated Current P-Plugs which are inserted in the N-buffer. At the forward conduction mode, the MCP act as the potential barrier to block the electrons flowing directly to the N+ anode, and the N-channels sandwiched between the MCP are fully depleted, which both increase the anode distributed resistance (RSA). In the turn off process, the N-channels provide three high-speed paths for minorities extraction, which reduces the turn off time. Consequently, the proposed device not only eliminates the snapback effect, but also achieves superior tradeoff between Eoff and Von. At the same Von of 1.6 V, it reduces the Eoff by 45%, 22%, and 14% compared with the VPN LIGBT, SSA LIGBT and NCA LIGBT, respectively. Meanwhile, it exhibits the lowest Von of 1.21 V at Eoff of 2 mJ/cm2.

Highlights

Lateral Insulated Gate Bipolar Transistor (LIGBT) is a promising power device, which is widely applied in High Voltage ICs (HVIC) [1,2,3,4]
It features three separated current P-Plugs P1, P2, and P3 under the P+ anode compared with the shorted anode (SA) LIGBT, and they are embedded in the N-buffer with the doping concentration
It can be seen that the proposed Multiple Current P-Plugs (MCP) LIGBT with P-Plugs n=3 can achieve the best tradeoff property, which can realize 45%, 22% and 14% reduction in Eoff at the same Von of 1.6 V compared with the Vertical P-collector and N-buffer (VPN) LIGBT, SSA LIGBT, and N-region Controlled Anode (NCA) LIGBT, respectively

Summary

INTRODUCTION

Lateral Insulated Gate Bipolar Transistor (LIGBT) is a promising power device, which is widely applied in High Voltage ICs (HVIC) [1,2,3,4]. The tradeoff relationship between forward voltage drop (Von) and turn-off loss (Eoff) limits the development of LIGBTs [5,6,7,8,9]. To address this issue, the shorted anode (SA) LIGBT is proposed to reduce the Eoff by providing an additional electron extraction path of the N+ anode [10,11,12,13]. A novel LIGBT with Multiple Current PPlugs (MCP LIGBT) in anode is proposed and investigated to eliminate the snapback, and achieve better trade-off between Von and Eoff. Wd (μm) Td (μm) Nd (cm-3) Wp (μm) Tox (nm) TBOX (μm) Nbuffer (cm-3) Np1, Np2, Np3

DEVICE STRUCTURE AND MECHANISM

RESULTS AND DISCUSSION

TRADEOFF CHARACTERISTICS

CONCLUSION